Hand-to-mouth

Those homeless people are living hand-to-mouth.

I'm sick of this hand-to-mouth existence.

She is living hand-to-mouth.

Tom is living hand-to-mouth.

She has been a widow these six or eight years, and has lived, I imagine, in rather a hand-to-mouth fashion.

The Migrant Fleet has little economic base, operating in a state of perpetual "hand-to-mouth". While quarian ships include light manufacturing and assembly plants, they lack heavy industries such as refining and shipbuilding. The fleet has tankers for water purification and oxygen cracking, but the space-intensive nature of agriculture limits food production. A single disaster could destroy the fragile balance.